Natural killer (NK) cells – fertility fraud?

Are natural killer (NK) cells really a threat to fertility and pregnancy? Clinics selling so-called reproductive immunology treatments say yes – or at least maybe. Others say no and ask for the research to back it up. Here’s the truth about natural killer cells. It may surprise you.

First, the case against. And it’s a strong one. Dr. Norman Shreeve, a highly regarded expert in obstetrics and gynaecology at the University of Cambridge, recently said: ‘There is no evidence to suggest that any currently available measurement of NK cells… can reliably guide treatment of fertility’. This is echoed by Professor Lesley Regan, another eminent figure in the fertility world, who can find no medical basis ‘to justify the use of these tests and treatments’.

Strong stuff. And a clear indictment of an industry aggressively offering fertility patients expensive ‘treatments’ and ‘therapies’ for natural killer cells. It’s well known that NK cells form part of the blood’s immune response to bacteria, viruses and cancers. But it’s highly questionable whether NK cells in the uterus – which do exist – attack in the same way as blood NK cells. More fundamentally it begs the obvious question: why on earth would a human uterus attack the embryo it is designed to nurture? The proposition seems preposterous.

As we’ve said before in this blog, natural killer cell therapy is an easy sell to anxious couples battling infertility. Just look at the prices being charged at UK clinics for the suppression, or down regulation, of uterine NK cells. We found one clinic charging £450 for a single intralipid infusion to ‘stabilise your immune system’. Destabilise your bank balance, more like – you need at least three infusions per treatment cycle. Or the private consultant charging £2,000 for intravenous immunoglobulin (IVIG) therapy. £2,400 for an NK uterine biopsy? £1,400 for a NK blood test? Welcome to the world of reproductive immunology – an entirely unregulated wing of the UK’s private fertility industry.

As Dr. Shreeve also points out, there’s no globally accepted reference range for uterine NK cell testing, making interpretation and comparison of results inconsistent. Blood NK testing for fertility is seemingly meaningless because there’s no clear link between blood NK cells and uterine NK cells. And suppressing the body’s immune system during pregnancy may have harmful side effects.

It’s only fair to mention the research in favour of natural killer cell treatment for fertility. There’s the small study from 2010 that suggested intralipids help patients who’ve had previous miscarriages (read our view on this). And the small study from Australia that found certain benefits in using the steroid Prednisone (read our view on that). And the small study from 2012, slightly supportive, into the use of immunoglobulin therapy on IVF patients with previous failures. And something a bit more promising from the University of Warwick in 2017.

It doesn’t amount to much, though the Warwick study has more meat on the bones. Other studies are less generous. No large-scale, randomized trials into NK treatment for infertility exist. The HFEA discredits it. But for the natural killer cell industry, glossily marketed and ready to take cash from fertility patients willing to try anything to boost their chances, it’s enough. And it’s only fair to suggest that, occasionally, immunological intervention might make a difference. Might. That hope is all the industry needs. Fertility treatment is, after all, a market in hope.

Some might argue that NK cell treatment providers should examine their consciences. Or at least the way they market and explain their services. Since that probably won’t happen, tighter regulation of largely unproven fertility treatments is needed. In the UK, the number of clinics and one-man bands charging absurd sums of money for NK treatments is troubling. All they have to do is provide a service with reasonable care and skill. That’s not the same as providing a service you actually need.

6 comments

Ead

After 4 miscarriages from natural pregnancies (all in 1st tri. and all with heartbeats) and seeing a couple OBs and REs, I was told by a RPL specialist RE that the reason for all my miscarriages was alloimmune dysfunction (partial DQ alpha match with my spouse and activated NKcells). The prognosis was for me to try IVF egg banking with PGS testing of embryos before transferring only 1 embryo at a time. I have now had 3 failed ivf banking cycles, which only yielded 2-4 eggs in each cycle. All eggs fertilized easily in all cycles but only one out of all 3 cycles made it to PGS testing and that was abnormal. I am thinking I made more progress trying on my own rather than going this route and am doubting the whole NK cells and partial DQ alpha diagnosis somewhat.

There are many many things wrong with NK testing and treatments. simply the tests do not reveal what causes miscarriage or implantation failure…no one knows what the NK tests are really doing in these couples. No one can agree on what is an abnormal test either. MAJOR PROBLEM there…how can one determine what to do and whom to treat if they cannot agree on what the tests do or what is normal/abnormal??? Then there is the treatment…put aside the sad problems of side effects like that noted above which can be devastating…simply the treatments DO NOT work to prevent miscarriage or IVF failure. The story above shows this clearly…and there are MANY like it, one only sees the stories where there have been sad failures the voila!. take intralipid and there is a pregnancy. that is not evidence. Shameless providers over the world seem to jump on board with something like this and dupe couples.

I had immunosuppression treatment privately in London out of sheer desperation, in conjunction wtih IVF treatment overseas, falling pregnant with twins.
As a nurse, i am well aware of the side effects of medication, but i did not expect to become seriously ill at 18 weeks and being diagnosed with septecaemia, required IV medication that has left me with stage 3 kidney disease. I also lost both of my girls short of 24 weeks.
I am happy to report 6 months after this i fell pregnant again having no immune treatment at all with FET from the same cycle, resulting in my gorgeous 2 year old son.

…to add to the above, my consultant said that the pregnancy in conjunction with the immune treatment had lowered my immune system to that of someone with HIV

November 29, 2015

gigi

Hi Jane,
I just want to say I am so sorry for the illness u suffered and the loss of your girls. At the same time it is great to hear u now have a son. I also have a son from IVF who is now 2.5 yrs old. I have just embarked on my 5th IVF to try for a second child. This will be our final attempt as I am now 43. I suffer with psoriasis and have been researching intralip treatment thinking maybe autoimmune issues were the reason for multiple failures. However, I have always been sceptical of anything that surpresses the immune system. After reading about your experience I will not be considering such treatment anymore. Also the fact I have a child from IVF (without intralips) suggests I do not need them and it was just bad luck that the other 4 cycles failed. Thanks for sharing your story. It has helped me make a decision.